The invention relates to improvements in a continuous fuel injection system. A fuel injection system is already known which operates at a relatively high pressure in order to avoid difficulties in restarting the internal combustion engine which may arise because of fuel evaporation taking place after the engine is turned off. This high pressure system makes great demands on the electric fuel pump, particularly insofar as wear thereof is concerned as well as the electrical power required, and consequent need for security against points of leakage.